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A variety of fungi, plants, and their different tissues are used in Traditional Chinese Medicine to improve health, and some of them are recommended for dietary therapy. Many of these plants and fungi contain antifungal proteins and peptides which suppress spore germination and hyphal growth in phytopathogenic fungi. The aim of this article is to review antifungal proteins produced by medicinal plants and fungi used in Chinese medicine which also possess anticancer and human immunodeficiency virus-1 (HIV-1) enzyme inhibitory activities., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Leguminous plants have formed a popular subject of research owing to the abundance of proteins and peptides with important biological activities that they produce. The antifungal proteins and peptides have been purified from a number of leguminous species. However, research continues to discover novel antifungal plant-produced peptides and proteins are being needed, specially those novel ones with both antifungal activity and other significant bioactivities. The objective of this study was to isolate a novel peptide from Phaseolus limensis. A 6.8 kDa peptide designated Limyin, with both antifungal and antiproliferative activity, was isolated from the large lima bean (P. limensis) legumes. The isolation procedure consisted of extraction, precipitation, affinity chromatography on Affi-gel blue gel, ion chromatography on SP-Toyopearl, and gel filtration on Superdex 75. Its N-terminal sequence was determined to be KTCENLATYYRGPCF, showing high homology to defensin and defensin precursors from plants. It potently suppressed mycelial growth in Alternaria alternata, Fusarium solani, and Botrytis cinerea. Its antifungal activity was stable up to 80 degrees C. It showed antiproliferative activity towards tumor cells including human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. However, it had no effect on bacteria Staphylococcus aureus and Salmonella. The present findings make a significant addition of the research on leguminous plants.

A protein designated Hypotin, with both antifungal and antibacterial activity, was isolated from peanut (Arachis hypogaea) seeds. The isolation procedure included extraction, ammonium sulfate precipitation, affinity chromatography on Affi-gel blue gel, ion chromatography, and gel filtration. The protein exhibited a molecular mass of 30.4 kDa in SDS-polyacrylamide gel electrophoresis under both reducing and nonreducing conditions, indicating that it is a monomeric protein. Its N-terminal sequence was highly homologous to those of chitinases and chitinase precursors from plants. It exerted potent antifungal action toward a variety of fungal species, including Pythium aphanidermatum, Fusarium solani, Physalospora piricola, Alternaria alternata, Botrytis cinerea, and Fusarium oxysporum. In addition, this novel protein exhibited antiproliferative activity against tumor cells. These findings further the progress in the research of leguminous plants.

Antifungal peptides with a molecular mass of 9 kDa and an N-terminal sequence demonstrating remarkable similarity to those of nonspecific lipid transfer proteins (nsLTPs) were isolated from seeds of the vegetable Brassica campestris and the mung bean. The purified peptides exerted an inhibitory action on mycelial growth in various fungal species. The antifungal activity of Brassica and mung bean nsLTPs were thermostable, pH-stable, and stable after treatment with pepsin and trypsin. In contrast, the antifungal activity of mung bean chitinase was much less stable to changes in pH and temperature. Brassica LTP inhibited proliferation of hepatoma Hep G2 cells and breast cancer MCF 7 cells with an IC(50) of 5.8 and 1.6 microM, respectively, and the activity of HIV-1 reverse transcriptase with an IC(50) of 4 microM. However, mung bean LTP and chitinase were devoid of antiproliferative and HIV-1 reverse transcriptase inhibitory activities. In contrast to the mung bean LTP, which exhibited antibacterial activity, Brassica LTP was inactive. All three antifungal peptides lacked mitogenic activity toward splenocytes. These results indicate that the two LTPs have more desirable activities than the chitinase and that there is a dissociation between the antifungal and other activities of these antifungal proteins., (Copyright (c) 2007 European Peptide Society and John Wiley & Sons, Ltd.)

A novel protease inhibitor, designated mungoin, with both antifungal and antibacterial activities, and exhibiting a molecular mass of 10kDa in SDS-polyacrylamide gel electrophoresis, was isolated from mung bean (Phaseolus mungo) seeds. The isolation procedure involved a combination of extraction, ammonium sulfate precipitation, ion exchange chromatography on CM-Sephadex, and high-performance liquid chromatography (HPLC) on SP-Toyopearl. Its isoelectric point was estimated to be 9.8 by isoelectric focusing. Its N-terminal amino acid sequence was determined to be EMPGKPACLDTDDFCYKP, demonstrating some resemblance to the C-terminal sequences of other protease inhibitors and inhibitor precursors from leguminous plants. It exerted a potent inhibitory action toward a variety of fungal species including Physalospora piricola, Mycosphaerella arachidicola, Botrytis cinerea, Pythium aphanidermatum, Sclerotium rolfsii and Fusarium oxysporum, as well as an antibacterial action against Staphylococcus aureus. In addition, this novel plant protease inhibitor displayed anti-proliferative activity toward tumor cells.

A chitinase with antifungal activity was isolated from mung bean (Phaseolus mungo) seeds. The procedure entailed aqueous extraction, (NH4)2SO4 precipitation, ion-exchange chromatography on CM-Sepharose, high-performance liquid chromatography (HPLC) on Poros HS-20, and gel filtration on Sephadex G-75. The protein exhibited a molecular mass of 30.8 kDa in SDS-polyacrylamide gel electrophoresis. Its pI was 6.3 as determined by isoelectric focusing. The specific activity of the chitinase was estimated to be 3.81 U/mg. The enzyme expressed its optimum activity at pH 5.4 and was stable from 40 to 50 degrees C. It exerted antifungal action toward Fusarium solani, Fusarium oxysporum, Mycosphaerella arachidicola, Pythium aphanidermatum, and Sclerotium rolfsii.

A novel lysozyme exhibiting antifungal activity and with a molecular mass of 14.4kDa in SDS-polyacrylamide gel electrophoresis was isolated from mung bean (Phaseolus mungo) seeds using a procedure that involved aqueous extraction, ammonium sulfate precipitation, ion exchange chromatography on CM-Sephadex, and high-performance liquid chromatography on POROS HS-20. Its N-terminal sequence was very different from that of hen egg white lysozyme. Its pI was estimated to be above 9.7. The specific activity of the lysozyme was 355U/mg at pH 5.5 and 30 degrees C. The lysozyme exhibited a pH optimum at pH 5.5 and a temperature optimum at 55 degrees C. It is reported herein, for the first time, that a novel plant lysozyme exerted an antifungal action toward Fusarium oxysporum, Fusarium solani, Pythium aphanidermatum, Sclerotium rolfsii, and Botrytis cinerea, in addition to an antibacterial action against Staphylococcus aureus.

Abstract: A novel lysozyme was isolated from the Canadian cranberry beans (Phaseolus vulgaris) and its enzymatic properties, antifungal and antibacterial activities were investigated. The isolation procedure involved aqueous extraction, ammonium sulfate precipitation, and chromatography purification including affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-Sephadex, and high performance liquid chromatography (HPLC) on Mono S. The enzyme exhibited a molecular mass of 15.6kDa in SDS-polyacrylamide gel electrophoresis both under reducing and non-reducing conditions, indicating that it was a monomeric protein. The 15N-terminal amino acid sequences were determined to be KVDMPGRFALAMQSH, showing some homology to hen egg white lysozyme. The pI was determined to be 9.6 by isoelectric focusing electrophoresis. The specific activity of the lysozyme was 652U/mg at pH 5.5 and 40°C. The lysozyme exhibited a pH optimum at pH 5.5 and a temperature optimum at 50°C. It exerted a potent inhibitory action toward fungal species including Alternaria alternata(Fr.) Keissl, Pythium aphanidermatum, Fusarium oxysporum and Botrytis cinerea, in addition to an antibacterial action against Staphylococcus aureus. However, it showed no effect on Gram-negative bacteria. The enzyme was thermostable below 58°C in both enzymatic reaction and antifungal activity. The present findings further the research on leguminous lysozyme with potentially exploitable significance. [Copyright &y& Elsevier]

Abstract: A novel chitinase with antifungal activity was isolated from fava bean (Vicia faba) seeds. The protein exhibited a molecular mass of 21.5kDa in reduced condition while 25.5kDa in oxidized condition on SDS-PAGE, indicating that there are disulfide bonds inside the molecule. Its N-terminal amino acid sequence was determined to be D-D-V-G-S-V-I-S-A-S-L-F-E-Q-L-L-K-H, showing homologous to those of chitinase and chitinase precursors from leguminous plants. The optimum pH and the optimum temperature for activity toward N-acetyl-d-glucosamine were 5.4 and 50°C, respectively. The pI was determined to be 8.7 by isoelectric focusing electrophoresis. The chitinase was thermostable up to 58°C in both enzymatic reaction and antifungal activity. It showed chitin-binding activity, suggesting that the catalytic domain is involved in the binding of chitinase to a certain extent. In addition, it exerted potent antifungal action toward a variety of fungal species including Pythium aphanidermatum, Fusarium solani, Physalospora piricola, Alternaria alternate, Botrytis cinerea, and Fusarium oxysporum f. sp. melonis. The present findings demonstrated a novel chitinase with disulfide bonds inside the molecule and show antifungal significance in agriculture. [Copyright &y& Elsevier]